Effects of rTMS Treatment on Cognitive Impairment and Resting-State Brain Activity in Stroke Patients: A Randomized Clinical Trial

Abstract

Background: Repetitive transcranial magnetic stimulation (rTMS) has been employed for motor function rehabilitation for stroke patients, but its effects on post-stroke cognitive impairment (PSCI) remains controversial. Objective: To identify the effects of rTMS intervention on PSCI patients and its potential neural correlates to behavioral improvements. Methods: We recruited 34 PSCI patients for 20 sessions of 10 Hz rTMS or nostim control treatments over the left dorsal lateral prefrontal cortex (DLPFC). Cognitive function was evaluated with the Montreal Cognitive Assessment Scale, Victoria Stroop Test, Rivermead Behavior Memory Test, and Activities of Daily Living (ADL) assessed with the Modified Barthel Index. 14 patients received functional MRI scan, a useful non-invasive technique of determining how structurally segregated and functionally specialized brain areas were interconnected, which was reflected by blood oxygenation level-dependent signals. The amplitude of low-frequency fluctuation (ALFF) and functional connectivity (FC) were applied as the analytical approaches, which were used to measure the resting-state brain activity and functional connection. Results: rTMS improved cognitive functions and ADLs for PSCI patients relative to patients who received no-stim control treatment. The cognitive improvements correlated to increased ALFF of the left medial prefrontal cortex, and increased FC of right medial prefrontal cortex and right ventral anterior cingulate cortex. Conclusion: 10 Hz rTMS at DLPFC could improve cognitive function and quality of life for PSCI patients, which is associated with an altered frontal cortical activity.

The Effect of Non-Invasive Brain Stimulation (NIBS) on Attention and Memory Function in Stroke Rehabilitation Patients: A Systematic Review and Meta-Analysis

“…Of these, all patients received rehabilitation regardless of the intervention group or control group. In rTMS, five studies combined cognitive rehabilitation and cognitive training [ 32 , 33 , 34 , 35 , 36 ]. Yin et al [ 34 ] and Lu et al [ 35 ] combined computer-assisted cognitive training in all patients [ 34 , 35 ].…”

“…In rTMS, five studies combined cognitive rehabilitation and cognitive training [ 32 , 33 , 34 , 35 , 36 ]. Yin et al [ 34 ] and Lu et al [ 35 ] combined computer-assisted cognitive training in all patients [ 34 , 35 ]. In tDCS, Shaker et al [ 37 ] and Yun et al [ 38 ] combined general rehabilitation with cognitive rehabilitation [ 37 , 38 ].…”

“…The 5 Hz rTMS group exhibited a superior modulating effect in attention compared to the iTBS group. Yin et al [ 34 ] reported that 10 Hz stimulation applied to the left DLPFC resulted in improved scores on the Montreal Cognitive Assessment (MoCA), Rivermead Behavior Memory Test (RBMT), and VST-B and -C compared to the control group [ 34 ]. They also examined rs-fMRI before and after the intervention in both groups.…”

“…The reason for choosing DLPFC was that all studies indicated that DLPFC was an important site in cognitive function. Some studies have shown that DLPFC is associated with WM [ 32 , 36 , 40 ], is an important part of the Default mode network [ 33 ], is a hub of attentional function [ 32 ], and plays an important part in the central executive network (CEN), which is responsible for high-level cognitive functions such as control of attention and WM [ 34 ]. Except for the study by Hosseinzadeh et al [ 41 ], excitatory stimulation of the frontal lobe was selected in tDCS studies [ 37 , 38 , 39 ].…”

“…In this systematic review, changes in brain activation were evaluated using neuroimaging and neuropsychological tests [ 33 , 34 ]. The common point in all is that a change in activity in the brain region was associated with the stimulation site.…”